The present invention relates to an apparatus for cutting or shredding a used one-time ink ribbon wound in a pancake form.
A one-time ink ribbon wound in a pancake form has a thermal transfer ink layer formed on one face of a base material. Parts of the ink layer are heated by a thermal head for transfer to recording paper. Thus, traces of print remain on the used ink ribbon which, if disposed of carelessly, could result in leakage of secret information.
Conventionally, therefore, used ink ribbons are cut to small pieces by means of shredders or the like.
Ink ribbons of th type noted above, however, are very thin having a thickness 5 to 20 micrometers, and besides the base material comprises a very soft plastic film. Such thin and soft ink ribbons just become bent at positions of contact with rotary blades of a thredder or the like. It has been practically impossible to reliably cut those ink ribbons to desired sizes.
Moreover, since such an ink ribbon has a great length, it is a very time-consuming operation to unwind the ink ribbon in a pancake form for shredding one portion after another.